CFexpress card recovery on Mac: how it differs from SD

A CFexpress card is not a bigger SD card. It's an NVMe solid-state drive in a small package, talking PCIe over the card's pins, and it behaves like one: fast, hot under load, managed by a controller with its own ideas about which blocks are free. The recovery steps look the same on the surface (stop using it, scan it, recover to another drive) but the details that decide whether you get your files back are different. This guide is about those details.

An SD card in a cheap USB reader works. A CFexpress Type B card in a cheap reader may not: some low-cost readers present the card through a USB bridge that stalls on read errors, drops the card when it gets warm, or caps throughput so low that a full-card scan takes hours. Use a reader from the card's manufacturer or a reputable one over USB 3.2 Gen 2 or Thunderbolt, and plug it directly into the Mac rather than through a hub. Type A cards (Sony) need a Type A reader; the slots aren't interchangeable.

If the card doesn't appear in Disk Utility's device list, try one other reader before assuming the card is dead. Reader failures are more common than card failures. If it doesn't appear in two readers, stop.

Cameras format CFexpress as exFAT, and the in-camera format is quick: it rewrites the boot region, allocation bitmap and root directory and leaves the data clusters in place. Deleted clips are simpler still; the directory entry is flagged deleted and the clusters stay reserved until reused. So far this is identical to SD.

The difference is file size. A single 8K RAW or 4K ProRes clip on CFexpress is routinely tens of gigabytes. exFAT stores a contiguous file with a single "no fragmentation" flag and no chain of cluster pointers, which is good for recovery when the quick scan can read the directory: one entry, one start cluster, one length, and the whole clip comes back. It's also why filling a card and deleting clips to make room, then recording again, fragments large files. A fragmented 40 GB clip carved by signature will have the wrong tail, and the repair step becomes important.

This is the biggest practical difference from SD. A CFexpress card under sustained read gets hot; a card that was already stressed (long takes, a camera that shut down for temperature) can start returning errors or disconnecting once it warms up during a scan. Every disconnect risks a partial scan and, on a card that's actually failing, makes the next attempt worse.

So: use DataRecover Pro's Create Image to make a byte-to-byte image of the card to a fast external drive with at least the card's capacity free. The image is read once, front to back, and bad regions are logged and skipped rather than retried. Then scan the image. You can run quick scan and deep scan against it repeatedly, unplug the card, and let it cool. On a healthy card over a good reader, imaging a 512 GB card is a matter of minutes at NVMe speeds; on a marginal one, it's the only approach that finishes.

If the card is too hot to hold, let it cool before imaging. If it disconnects repeatedly even when cool, that's a controller or flash fault and a lab is the next step.

Because CFexpress is an SSD, the controller may erase blocks it believes are free. Cameras generally don't issue TRIM commands, so a card formatted or deleted in-camera keeps its data the way an SD card does. But if you formatted the card in Disk Utility, or erased it with a tool that issues TRIM, or the card's own garbage collection has run over the freed blocks, that data can be genuinely gone, and no scan will find it. Whether TRIM was issued isn't something you can check after the fact; run the scan and see. The same caveat applies to any SSD, and it's covered in APFS SSD recovery and TRIM.

Quick scan first. It reads the exFAT directory and allocation bitmap and, for deleted or quick-formatted cards where the entries survive, returns clips and stills with their names, folder paths, and correct lengths. This is the path that returns a 40 GB clip whole. Recover to a different drive with enough room.

Deep scan if the quick scan is empty. It carves MP4/MOV (including ProRes in MOV containers and Canon CR3, which shares the `ftyp` signature), HEIC, JPEG, and the TIFF-based RAWs with their maker-specific extensions, sizing each file from its own structure rather than guessing. Filenames are lost in this path. Video in the results grid shows metadata; Quick Look will play recovered clips before you save them. Photos show thumbnails. Both are free and need no account. Download DataRecover Pro.

If the card isn't detected in two known-good readers, or shows the wrong capacity, the controller has failed and software can't reach the flash. If the card was erased with a tool that issued TRIM, the blocks are gone. If you recorded over the space (the card was formatted and used for another shoot), the earlier footage is overwritten. And if a clip was interrupted mid-recording rather than deleted, it's on the card but has no index; that's a repair job, covered in recovering ProRes and 4K MOV after a recording stopped mid-clip.